Here you can perform a case insensitive search for usernames. If you would like to match part of the username, use * (an asterix) as a wildcard. Checking the Regular Expressions box will allow you to search based on your regex pattern.

E-mail address: Regular Expression?

Enter an expression to match a user's email address. This is case insensitive. If you want to do a partial match, use * (an asterix) as a wildcard. Checking the Regular Expressions box will allow you to search based on your regex pattern.

Userfield: Regular Expression?

Search for users based on various profile fields. Wildcards are supported using an asterix (*). Checking the Regular Expressions box will allow you to search based on your regex pattern.